Cellulose-ether solvent and composition



Patented Oct. 9, 1923.

.STEWART 3'. CARROLL, OF ROCHESTER, NEW YORK, ASSIGNOE TO KODAK COMPANY,OF ROCHESTER, NEW YORK, A. CORPORATION OF NEW YORK.

CELLULOSE-ETHEB SOLVENT AND COMPOSITION.

No Drawing. Application filed April 1,

To all whom it may concern:

Be it known that I, STEWART J. CARROLL,

a citizen of the United States of America,

residing at Rochester, in the county of 5 Monroe and State of New York,have invented certain new and useful Improvements in Cellulose-EtherSolvents and Compositions, of which the following is a full, clear, andexact specification.

This invention relates to solvents for making strong solutions ofcellulose ether and also relates to the cellulose ether compositionsproduced by the aid of such solvents. One object of m invention is toprovide a l solvent which Wlll dissolve such large pro portions ofcellulose ethers that thick or viscous flowable solutions may beobtained for use in plastic and film making arts.

Another object of my invention is to provide a cellulose ether solutionwhich may be matnufactured into strong, flexible transparent film on themachines and by the methods now in use.

InU. S. Patent No. 1,188,376, Lilienfeld,

June 20, 1916, there are disclosed a series of alkyl ethers ofcellulose. Certain of these are practically insoluble in water, and myinvention relates, but is not limited, to the ethers having thatproperty. While the ethers form thin solutions-in the lower monohydroxyaliphatic alcohols and in certain aliphatic ketones, it has been foundthat such single solvents by, themselves do not dissolve a sufiicientproportionof the ethers to make a desirably thick flowable compositionordope, such as may be used in the manufacture of photographic film base,for instance, by customary methods, or in the other plastic arts.

I have discovered that an adequately strong and useful solvent may beprepared b mixing one or more of the lower alip atic ketones having morethan 3 carbon atoms with one or more of the lower monohydroxy aliphaticalcohols. By the latter term I include the members of the series havingless than six carbon atoms. As a few examples of such ketones, I maymention methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone,methyl amyl ,the process of film manufacture,

1921. Serial 110. 457,121.

-diisopropyl ketone, dibutyl ketone, diamy ketone, etc. Generally I usea mixture of these ketones, such being found commercially in theso-called acetone oils. By way of illustration, I ma mix equal parts byweight of acetone oi and methyl or ethyl alcohol. or a mixture of them.

'While the amount of ether that may be dissolved in such mixed orcompound solvents may be varied as desired over a large range, it isnoted, for the sake of example, that 1 part by weight of water-insolubleethyl cellulose when dissolved in 5 parts of one of the above compoundsolvents yields a thick viscous flowable solution.

' Other substances which impart additional suppleness, orincombustibility, or other qualities, to the dope, such, for instance,as triphenyl or tricresyl phosphate, camphor, etc. Since the acetone oilcontains several ketones of relatively higher boiling point andcorrespondingly lower volatility, such ketones remain in considerableamounts in the film when the more volatile lower ketones and alcoholsevaporate. The ketones remaining in the film impart useful properties toit.

The ingredients are ofthe ordinary commercial type and sufficientlypurified for so as to give a dope yielding films having the properrelative freedom from color. The viscous-flow-able dope above describedcan be used in connection with' the usual filmforming apparatus withoutthe necessity of expensive alterations in-the latter.

Havin thus described my invention, what I c aim as new and desire tosecure by Letters Patent-is;

1. A composition of matter, comprising cellulose ether, a aliphaticketone containing more than 3 carbon atoms, and a lower monohydroxyaliphatic alcohol.

2. A viscous flowable composition, comprising an alkyl ether ofcellulose dissolved in a solvent containing approximately e ual parts byweight of acetone oil and a 1 ,er monohydroxy aliphatic alcohoL- 3. Acomposition of matter, comprising the film may also be added to g2,Laeaera Water-insoluble ethyl cellulose, acetone oil and a'aliphaticketone containing more than 16 and methyl alcohol. 3 carbon atoms.

' 4-. A composition of matter, comprising 7. As an article ofmanufacture, a flowed cellulose ether and a aliphatic ketone conordeposited flexible transparent film, com- 5 taining more than 3 carbonatoms. prising a Water-insoluble ether of cellulose 5. A composition ofmatter, comprising and acetone oil, 21a cellulose ether and acetone oil.Signed at Rochester, New York, this 26th 6(As an article of manufacture,a flowed day of March, 1921. or deposited film, comprising celluloseether STEWART J. CARROLL.

